There are many different folding devices using cams, levers, ploughs and other such mechanisms to fold the flaps of a carton from an open position to a close position and to, if desired, seal the carton, for example, by preapplied adhesive or by tapes applied over the close flaps. Most of these devices include a movable plough position on the path of movement of the carton being closed and activated either pneumatically or electrically or hydraulically to force the plough in a looping action moving faster than the transported carton to fold the rear flap forwardly into a position substantially perpendicular to the rear wall. At about the same time a fixed front plough folds the front flaps substantially perpendicular to the front wall by movement of the carton relative to the plough. After the front and rear flaps have been folded the carton generally moves to another position wherein ploughs engage each of the side flaps and folds them over onto the prefolded front and rear flaps to close the carton. It will be apparent that the front and rear flaps must be folded before folding of the side flaps may begin, therefore, the carton must move along a relatively long path past stationary ploughs during the closing operation thereby requiring a relatively large piece of equipment.
In some closing systems, relatively complicated controls are required to actuate and time the actuation of the various stops, ploughs, and levers, etc.
In some of these devices, side conveyors (i.e. conveyors positioned on each side of the carton passage and that grip (by friction) each side of the carton) are used to move the carton through the passage. It will apparent that the direction movement of the conveyor belt on one side of the passage is in one direction and of the belt on the other side is in the opposite direction, i.e. the drive roller on one side of the carton passage rotates in the clockwise direction while the one on the other side rotates in the counterclockwise direction. A suitable drive for such a belt conveyor system is shown in U.S. Pat. No. 4,161,138 issued Jul. 17, 1979 to Marchetti. This drive requires that the width of the machine be extended, which obviously detracts significantly from the compactness of the equipment and is a detriment when space requirements are the premium.